Onset and melting of local orbital order

Department of Physics, Indian Institute of Technology, Kanpur, India.
Journal of Physics Condensed Matter (Impact Factor: 2.35). 02/2012; 24(8):086003. DOI: 10.1088/0953-8984/24/8/086003
Source: arXiv


The onset and melting of locally staggered charge/orbital correlations is investigated within a two-orbital correlated electron model with inter-orbital and inter-site Coulomb interactions. The CE-type orbital correlation exhibits a sharp onset close to the Curie temperature and rapid thermal melting thereafter, which provides quantitative understanding of the (π/2,π/2,0) feature observed in neutron scattering experiments on La(0.7)(Ca(y)Sr(1-y))(0.3)MnO(3) single crystals. In the zig-zag AF state, the CE-type orbital correlations are found to be even more readily stabilized, but only within a narrow doping regime around x = 0.5.

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